Online shoppers interact with electronic commerce network sites to find products of interest and obtain information about those products. Such sites may allow users to interact with a network page in a browser in order to browse a catalog hierarchy, sort items by various criteria, perform searches using keywords, and perform various other actions. In doing so, the user accesses or views a series of pages, moving from one page to another. To view these pages, each page is retrieved, which includes layout code and any content referenced by the page.